Tone-arm support



' May 1, 192.3. 1,453,613 1.. R. WOLFF TONE ARM SUPPORT Filed Sent. 291921 Patented May 1, 1923. v

UNITED STATES LORENZ nfwoLrr, or Los ANGELES, CALIFORNIA.

TONE-ABM surroa'r.

Application filed September 29, 1921. Serial No. 504,076.

To all whom it may concern Be it known that I, LORENZ R. l/VoLFF, acitizen of the United States, residing at Los Angeles, county ofLosAngeles, and State of California, have invented a new and usefulTone-Arm Support, of which the following is a specificatio'n.

My invention relates to phonographs and more particularly to a tone armsupport for the same.

Phonographs as at present manufactured are provided with a reproducercarried at 'the forward end of a hollow arm which is universally pivotedto a tone arm bracket mounted in the tone chamber of a phonograph.

In some instruments it is the practice to support the entire'weight ofthe tone arm and reproducerfon the playing point of the needlethat restson the record during the playing of the record. This is injurious to therecord, the needle, and quality of tone produced.

Some manufacturers of phonographs recognized this injurious effect andhave tried to overcome its effect by shortening the pivoted length ofthe tone arm. This construc tion was also faulty inasmuch as thecombined weight of the reproducer and that 39 part of the tone arm infront ofthe pivot point carrying the reproducer is too heavy.

In a tone arm support produced according to my invention, as much weightas desired can be brought to bear upon the record at the point ofreproduction, which is, where the needle is in contact with the recordgroove. I A 1 In records ofthe type inwhich the sound impressions arerecorded in the side of thegroove, it is only necessary to apply enoughweight at the point of reproduction to make the needle follow thegroove. I have found that by the use of my tone arm support I can adjustthe weight at the point of production to such a degree that all scratchynoises heretofore produced, especially by records containing grit, aregreatly eliminated.

In the reproduction of records that have become warpedyby the action ofheat and time, the rise and fall of the undulations are followedperfectly by. a tone arm provided.

with my support and no apparent difference in reproduction from thatproduced by, a

5 flat record is noticed.

One of'the principal objects of my invenlow the undulating or unevensurfaces of a' phonograph record.

Other objects and advantages w ll be made evldent hereinafter.

Referring to the drawing which is for il-- lustrative purposes only,

Fig. 1 -is a side elevation of a phonograpl tone arm provided with mysupport.

Fig. 2 is a top plan view of my tone arm support shown-attached to thetone arm mounting. Fig. 3 is a sectlon on line 33 of Fig. 2.

Fig. 4 is a section on line 1-1 of Fig 2.

Fig. 5 isa section of the adjusting nut on line 55 of Fig. 2.

Fig. 6 is a face view of the tone arm supporting yoke.

Fig. 7 is avertical sectional view of the supporting post for the tonearm and rela ted parts.

The tone arm 5 consists of a horizontally disposed cylindrical memberhaving mounted thereon at the outer end a reproducer 6 which carriestheneedle 7, such needle belng shown 1n engagement with a record 8. Theinner end of the tone arm terminates 1n a vertically disposed portionhaving a rounded end which is pivotally mounted on a pin 9 supported ina collar 13 which is revolvably mounted in the tone arm post 10. Astationary bracket'11 is securedsby screws 12 to the revolvable collar13 of the arm post 10, which post 10 is secured to the top board 15 ofthe phonograph. 'Pivotally mounted on trunnion screws 16, in ears 17,1on the bracket 11 is a carrying arm 18. Thecarrying arm 18 is providedwith resilient supporting means for the tone-arm which consist of a yoke20 mounted on the outer ends of wire springs 21. The springs slidablyextend through holes 23 in a downwardly depending flange 24 formed onthe carrying arm 18 and have their inner ends fixed in the clamping nut29 drawing'the block 25 tightly against the under side of the arm 18when the nut is screwed down on the stud 26.

c Interposed between the bracket 11 and i the arm 18 isan adjustablespring 30. The

' lower end of the spring 30 is provided with a plug 32 in which isrevolvably secured the reduced end of a threaded stud 33 provided with alock nut 34 and a knurled head35. The stud 33 may be screwed up or downin the threaded outer end 36 of the bracket '11 and locked in anydesired position by the lock nut 34.

The yoke 20 consists of a block 40 into which the outer ends of thesprings 21.are secured and a U shapedthroat or supporting member 41 forthe .outer end 0 the tone arm.; v

The inner face of the throat 41 is preferably made half round so as toofier the least frictional resistance to that part of the tone armresting upon the same,

The operation of my tone arm support is as follows: 1

' en a phonograph tone arm and its component parts are assembled, it hasbeen found in practice, that. the 'variation of weight in'these partsproduce a variation of tone q uality.

By ad usting the distance between. the arm 18 and the outer end of thebracketll, so that-the spring 30 will almost counterbalance the weightof the tone arm and then volvable collar on said adjusting the length ofthe springs-21 so that the required resiliency is given the tone arm anideal -condition is acquired.

I have found in practice that records used on a phonograph provided withmy tone -arm support, .show no perceptible wear after such use and thatthe steel needle which ordi narily can only be used with success ,forone or two reproductions may beused in connection with my device manytimes.

e llhave shown and described my invention as applied to a single piecetone arm it is to be understood that my tone arm support may be used onvarious types of tone arms whether made in one piece or of jointed typeswithout departing'from the Spirit of my invention.

' ll claim as my invention:

1. in combination, a tone arm post, a rest, a tone arm pivotally mountedin said collar, a .bracket fixed to said collar, an arm pivotallymounted on said bracket, apair of wire springs slidably extendin througha portion of said arm, means or fixingsaid springs to said arm, a yokefixed to the outer end of said springs arranged to receive and supportthe outer end of said tone arm, a coiled spring interposed between saidarm and said bracket and means forvarying the tension on said coiledspring.

2. In combination, a tone arm'post, a revolvable collar on said post, atone arm pivotally mounted in said collar, a bracket fixed to saidcollar, an arm pivotally mounted on said bracket; a yielding memberslidably mounted on said arm, meanson said member for supporting saidtone arm, a coiled spring interposed between said arm and said bracketand meansv for varying the tension of said coiled spring;

3. In combination, atone arm post, a revolvable collar on said post, atone arm pivotally mounted in said collar, a bracket fixed to saidcollar. an arm pivotally mounted on said bracket, a pair of wire springsslidably extending t rough a portion of said arm, means for xing saidsprings to said arm, a yoke fixed to the outer end of said springsarranged to receive and supportthe outer end of said tone arm, and ayielding member interposed between said arm and said bracket.

4. In combination, a tone arm post, a revolvable collar on said post, atone arm pivotally mounted in said collar, a bracket fixed to saidcollar, an arm pivotally mount-' ed on said bracket, a yielding membermounted on saidarm, means on said member for supporting said tone arm,and a yielding member interposed between said arm and said bracket.

5. In combination, a tone arm post, a revolvable collar on sald post, atonearm pivotally mounted in said collar, a bracket mounted on saidcollar, ayielding member pivotally mounted on said bracket-to swingvertically thereon, means on said yielding member arranged to engage andsupport the outer end of said (tone arm, and means for garying thetension'on said yielding memv 6. In combinationja tone arm support, atone arm pivotally and revolvably mounted in said support, a bracketmovable with said tone arm, an arm pivotally mounted on said brackettoswing vertically thereon, and a yielding member mounted on said armarranged to yieldingly support the outer and of said tone arm. Intestimony whereof. I have hereunto se my hand atLos' Angeles,California, this 21st day of September 1921.

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